CPG-free gene for a new secreted reporter protein

Abstract

A synthetic gene devoid of CpG nucleotide derived by genetic engineering from copepod luciferases genes that code for a new secreted luciferase with a strong bioluminescent signal. This gene display advantageous properties to be used as a reporter genes in cell based assays.

The invention claimed is: 
     
       1. An isolated nucleic acid molecule, the nucleic acid encoding a preprotein comprising:
 a signal peptide; and 
 a protein having luciferase activity, 
 wherein, said nucleic acid molecule is devoid of CpG, and said protein having luciferase activity comprises an amino acid sequence having at least 95% identity to the amino acid sequence set forth as SEQ ID NO: 3. 
 
     
     
       2. The isolated nucleic acid molecule according to  claim 1 , comprising the nucleic acid sequence set forth as SEQ ID NO: 1. 
     
     
       3. The isolated nucleic acid molecule according to  claim 1 , wherein said protein having luciferase activity comprises the amino acid sequence having at least 95% identity to the amino acid sequence set forth as SEQ ID NO: 3 when the said protein is secreted from cells. 
     
     
       4. An expression vector, comprising the nucleic acid molecule according to  claim 1  operatively linked to a promoter. 
     
     
       5. The expression vector according to  claim 4 , wherein the promoter is devoid of CpG. 
     
     
       6. The expression vector according to  claim 4 , wherein the promoter is an interferon inducible promoter. 
     
     
       7. The expression vector according to  claim 4 , wherein the promoter is inducible by an alpha interferon, a beta interferon or a lambda interferon. 
     
     
       8. The expression vector according to  claim 4 , wherein the promoter is an IL28 inducible promoter. 
     
     
       9. An isolated cell transformed with the nucleic acid molecule according to  claim 1 . 
     
     
       10. The cell according to  claim 9 , wherein the protein encoded by said nucleic acid molecule is secreted by the cell. 
     
     
       11. The cell according to  claim 9  further comprising a reporter gene. 
     
     
       12. The cell according to  claim 11 , wherein the reporter gene is a secreted embryonic alkaline phosphatase (SEAP) reporter gene. 
     
     
       13. The cell according to  claim 12 , wherein the reporter gene is devoid of CpG. 
     
     
       14. A kit comprising:
 the nucleic acid molecule according to  claim 1 , an expression vector comprising the nucleic acid molecule, or an isolated cell transformed with the nucleic acid molecule or an expression vector comprising the nucleic acid molecule, and 
 a substrate of the protein having luciferase activity encoded by the nucleic acid molecule. 
 
     
     
       15. The kit according to  claim 14 , wherein the nucleic acid molecule comprises the nucleic acid sequence set forth as SEQ ID NO: 1. 
     
     
       16. An isolated cell transformed with the expression vector according to  claim 4 . 
     
     
       17. The isolated nucleic acid molecule according to  claim 1 , wherein said protein having luciferase activity comprises an amino acid sequence having at least 98% identity to the amino acid sequence set forth as SEQ ID NO: 3. 
     
     
       18. The isolated nucleic acid molecule according to  claim 1 , wherein said protein having luciferase activity comprises the amino acid sequence set forth as SEQ ID NO: 3. 
     
     
       19. The isolated nucleic acid molecule according to  claim 1 , wherein the signal peptide comprises the sequence of amino acids 1-17 of SEQ ID NO: 2. 
     
     
       20. The isolated nucleic acid molecule according to  claim 1 , wherein said preprotein comprises the amino acid sequence set forth as SEQ ID NO: 2.